$OpenBSD: patch-src_log_cpp,v 1.1 2017/04/30 08:56:45 espie Exp $
--- src/log.cpp.orig
+++ src/log.cpp
@@ -30,6 +30,7 @@ Foundation, Inc., 59 Temple Place, Suite 330, Boston, 
 #include <stdexcept>
 #include <SDL.h>
 
+using dd::mutex;
 
 struct log_msg
 {
